A cord (50) comprises a single layer (52) of helically wound metal filamentary elements (54). The metal filamentary elements define an internal enclosure (58) of the cord of diameter Dv. Each metal filamentary element (54) has a diameter Df and a helix radius of curvature Rf. With Dv, Df and Rf being expressed in millimetres, the cord satisfies the following relationships: 9≤Rf/Df≤30 and 1.30≤Dv/Df≤2.10.

A steel cord with a construction of m+n having a first group of core filaments having a number of m and a second group of sheath filaments having a number of n, the second group and the first group are twisted around each other with the same twist pitch and same twist direction, wherein the core filaments are not twisted with each other, the core filaments are parallel or have a twist pitch being more than 300 mm, and the sheath filaments have a twist pitch being less than or equal to 30mm, the core filaments have an average tensile strength Tc in MPa when being un-ravelled from said steel cord, the sheath filaments have an average tensile strength Ts in MPa when being un-ravelled from said steel cord, Tc and Ts satisfy: 5<(Tc-Ts)<200. The steel cord has high breaking load and high production efficiency without cost increase.

A steel cord with a construction of m+n having a first group of core filaments having a number of m and a second group of sheath filaments having a number of n, the second group and the first group are twisted around each other with the same twist pitch and same twist direction, wherein the core filaments are not twisted with each other, the core filaments are parallel or have a twist pitch being more than 300 mm, and the sheath filaments have a twist pitch being less than or equal to 30mm, the core filaments have an average tensile strength Tc in MPa when being un-ravelled from said steel cord, the sheath filaments have an average tensile strength Ts in MPa when being un-ravelled from said steel cord, Tc and Ts satisfy: 5<(Tc-Ts)<200. The steel cord has high breaking load and high production efficiency without cost increase.

Provided is a steel cord for rubber article reinforcement which has excellent corrosion resistance and productivity without deterioration of adhesion with rubber. A steel cord (1) for rubber article reinforcement, in which plural steel filaments (2) are twisted together, includes: a core having at least one core filament (2c); and a sheath having at least one sheath layer formed by twisting at least one sheath filament (2s) around the core. In this steel cord (1), brass plating is performed on the steel filaments (2) and zinc plating is further performed on the outer circumference of the brass plating of the core filament (2c), and the steel filaments (2) have a diameter d of 0.1 mm to 0.6 mm.

Provided is a steel cord for rubber article reinforcement which has excellent corrosion resistance and productivity without deterioration of adhesion with rubber. A steel cord (1) for rubber article reinforcement, in which plural steel filaments (2) are twisted together, includes: a core having at least one core filament (2c); and a sheath having at least one sheath layer formed by twisting at least one sheath filament (2s) around the core. In this steel cord (1), brass plating is performed on the steel filaments (2) and zinc plating is further performed on the outer circumference of the brass plating of the core filament (2c), and the steel filaments (2) have a diameter d of 0.1 mm to 0.6 mm.

The subject of the invention is a cord (50) comprising a single layer (52) of helically wound metal filamentary elements (54). The metal filamentary elements define an internal enclosure (58) of the cord of diameter Dv. Each metal filamentary element (54) has a diameter Df and a helix radius of curvature Rf.

With Dv, Df and Rf being expressed in millimetres, the cord satisfies the following relationships:

9≤Rf/Df≤30, and

1.30≤Dv/Df≤2.10.

The subject of the invention is a cord (50) comprising a single layer (52) of helically wound metal filamentary elements (54). The metal filamentary elements define an internal enclosure (58) of the cord of diameter Dv. Each metal filamentary element (54) has a diameter Df and a helix radius of curvature Rf.

With Dv, Df and Rf being expressed in millimetres, the cord satisfies the following relationships:

9≤Rf/Df≤30, and

1.30≤Dv/Df≤2.10.

Pneumatic vehicle tire of radial type of construction, in particular a commercial vehicle tire, having a belt assembly (3) made up of at least three plies (8, 9, 10), namely two working plies (8, 9) and a protective ply (10) arranged radially on the outside with respect to the working plies (8, 9), wherein the protective ply (10) has reinforcing members (11) made up of one or more twisted-together steel filaments (12), wherein the steel of the steel filaments (12) of the reinforcing members (11) of the protective ply (10) can be assigned to the strength class ST or to a higher strength class, wherein the strength class ST has a tensile strength in MPa of 3980-2000 d and the strength class UT has a tensile strength in MPa of 4400-2000 d, wherein d is the diameter of a steel filament in mm.

Pneumatic vehicle tire of radial type of construction, in particular a commercial vehicle tire, having a belt assembly (3) made up of at least three plies (8, 9, 10), namely two working plies (8, 9) and a protective ply (10) arranged radially on the outside with respect to the working plies (8, 9), wherein the protective ply (10) has reinforcing members (11) made up of one or more twisted-together steel filaments (12), wherein the steel of the steel filaments (12) of the reinforcing members (11) of the protective ply (10) can be assigned to the strength class ST or to a higher strength class, wherein the strength class ST has a tensile strength in MPa of 3980-2000 d and the strength class UT has a tensile strength in MPa of 4400-2000 d, wherein d is the diameter of a steel filament in mm.

A steel cord for rubber reinforcement comprises a first group of core filaments (105) having a number of m and a second group of sheath filaments (110) having a number of n, m is three or four, the core filaments (105) are forming a helix, the core filaments (105) are not twisted together and being substantially parallel or the core filaments (105) have a twist pitch being more than 300 mm; the second group and the first group are twisted with each other, and the sheath filaments (110) are forming a flattened helix in the same direction of the helix of the core filaments (105), and the sheath filaments (110) have a cord twist pitch, at any cross-section of the steel cord, at least one interstice between two adjacent core filaments (105) is present. The steel cord has improved abrasion resistance and can contribute to the reduction of the weight of the tire.